Insect electrocutor



4 mg. 16, 1932. w. M. FROST 1,871,978

INSECT ELECTROCUTOR a FEJQE.

Aug. 16, 1932. w. M. FROST INSECT ELECTROCUTOR Filed Jan. 14, 1928 2Sheets-Sheet 2 Patented na is, than stares t int INSECT ELECTEOGUTGEApplication filed January it, 1923. Serial No. 2%,840.

My invention relates to insect electrocutors and particularly to devicesof this character which comprise spaced wires or other conductorsadapted to be charged with an electric a current and to electrocuteinsects which come into contact with or in close proximity to the wires.

Tnsect electrocutors of this general type have heretofore been formed ofalternately is positioned and suitably insulated positive and negativeelectric wires or conductors, examples of devices of this kind beingdisclosed in Letters Patent No. 974,7 85, granted to me on November 8,1910.

The conductor elements employed in such devices may be positioned andarranged in various ways. Forexample, they may consist of only a pair ofcontinuous conductors looped or bent to form a plurality of lengths orruns; or they may be in the form of relatively shorter separateconductors provided with suit-able electrical connections at their ends.In whichever way the lengths or runs of the conductor elements areprovided they are capable of a variety of modes of arrangement. They maybe disposed horizontally, or vertically, or at any desired angle. Or,when suitably insulated, vertical and horizontal wires may be crossed,with or without oblique wires or conductors, to present a gridformation, which may also be produced by crossed oblique conductors, orby combining oblique conductors with either the horizontal or verticalconductors in similar fashion I have found it preferable, however, toarrange all of the conductors or lengths or runs of the conductors insubstantially arallel relation, and in the same plane, or su stantiallyso, as in the forms of devices shown in my former Patent No. 974,7 85.

The parallel lengths or runs are preferably so arranged that alternateones will be charged with currents of opposite polarity, and so spacedfrom one another that a normally open circuit may be completed throughadjacent conductors or lengths of conductors by the body of an insectwhich comes into contact with the charged conductors or into theelectrostatic field which is created be- 50 tween the conductors and foran appreciable device is to be installed and used. The wire distancebeyond the plane in which they lie. in devices of this character and,general construction heretofore blown or used, the conductor elementsmore or less generally employed have been in the form of ordinary plainstraight wire. This wire is ordinarily stretched upon a frame or betweensuitably spaced supports, according to the requirements of theparticular situation in which the lengths or runs of necessity have beenplaced sufficiently close together to have the electrostatic fields ofopposite polarities cover practically the entire space between thewires, in order to prevent the passage of small insects through thedevice between the wires without being electrocuted.

Under certain conditions, as, for example, where the device is to bemade in the form of a screen, particularly for use in show windows,doors, transoms or the like, it is desirable to use fine wire, since thewires are not readily visible and form a screen which is substantialltransparent. Furthermore, wires of this kind may be charged with arelatively high tension current or static charge, so that insects willbe electrocuted if they merely pass between adjacent wires withoutcoming into contact with either of them. In order to accomplish thisresult however the wires must be comparatively close together; the bestresults I have found to be obtained by spacing the wires approximatelyonly it; of an inch apart, when from 24 to 28 gauge wire is used.

When ordinary plain straight wires are placed so close to ether, theelectrostatic field created beyon the plane of the wires is considerablyless, both as todepth' and intensity, than can be obtained by spacingthe wires farther apart. The field created when the wires aresufficiently close together to insure against the passage. of insectsbetween them is'insufiicient, in fact, to accomplish the electrocutionof the insects at a distance from the screen, as can be effected where adeeper and stronger electrostatic field exists. As a result, insectsapproaching the wires are in many cases not affected until they actuallycome into contact with the wires. The burn- 1 ing of insects upon thewires of the screen is objectionable, for the reason that the screen maybecome fouled and clogged, and rendered unsightly and less efficient.

I have also discovered that, where the conductor elements of the screenare plain straight'wires, and are as close together as is required toprevent the passage of insects between them, it is practicallyimpossible to maintain the wires in their required spaced relationwithout the aid of some means for exerting a constant tension upon them.However taut the wires may be stretched when they are placed upon theirframe'or other support, and however exactly they may then be positionedand spaced, they cannot be depended upon to maintain an accurate or evenoperative spaced relationship under all conditions of temperature andclimate. It has been found that, when exposed even to ordinarily highatmospheric temperatures, the wires will lengthen and sag to such anextent and so irregularly that adjacent wires of opposite polarity willcontact and short circuit the device, thus rendering it inoperative.

One of the principal objects of my invention is the provision of aninsect electrocutor which will possess all of the advantages of devicesof similar character heretofore known or used, and which will, atinsignificant additional cost, if any, have a wider field of influenceto attract insects to the device and will possess a considerably moreextended and more powerful electrocutive action.

A further object of my invention is the provision of an insectelectrocutor comprising spaced wires or conductors so fashioned, shaped,constructed and arranged as to be capable of being positioned in closejuxtaposition and yet creating, when charged with electric current, asuction or attraction of insects toward the wires, and the electrocutionof the insects before they come into contact with the wires.

A further object of the invention is the provision of an insectelectrocutor composed of wires or conductors of such form, configurationor construction as to effect the holding of the conductors securely intheir assembled relation with the desired tautness, without the aid ofseparate holding, securing, or tensioning devices, and withoutmaterially increasing the difficulty or cost of manufacture or assemblyof the device. In fact, the omission of the heretofore essentialseparate tension devices for the wires tends both to cheapen and tofacilitate production.

These objects and advantages are attained by the use of wires, thinmetallic strips or ribbons, or other conductors of a particular form,construction and configuration. The desired effects are produced byemploying conductor elements which have incorporated or produced in thema series of bends throughout their entire length or a substantialportion thereof. These bends may be in the form of crimps, waves orcorrugations, placed in the conductor by dies or other suitable meanswell known in the art. Or the bends may be produced by giving theconductor a spiral or helical form throughout its entire length or apart or parts thereof. As a result of such bending of the conductors,they are made to possess the characteristics of springs, being given apositive and substantial longitudinal resiliency by virtue of which theytend to return to their original condition when stretched. Conductors soformed, when stretched and secured in their elongated condition upon asupport or supports will tend to shorten themselves, thus exerting apull upon the support at their points of attachment, and constantlymaintaining a high degree of tension in the conductors themselves.

By this means the proper tensioning of the conductors is obtained, andadjacent conductors or adjacent lengths or runs of conductors aremaintained uniformly spaced from one another throughout the width orlength of the device, irrespective of temperature or other climaticconditions. Thus, the use of separate tensioning devices is madeunnecessary. This, in itself is an important advantage.

Of even greater importance,however, are the widening of the scope ofaction of the device and its increased effectiveness. Because of theconfiguration of the conductors the current through them creates greaterinductance and establishes anelectrostatic field on each side which isconsiderably more extensive and intensive than would be obtained if thecurrent were passed through plain straight wire such as has heretoforebeen used in devices of this character. The electrostatic field, it hasbeen observed, is deepest and strongest immediately beyond the points orconvex sides of the bends, at which points the condition of thesurrounding atmosphere is most affected, and electrical discharges tendmost strongly to occur.

One of the greatest advantages arising from my present invention is dueto the effect thus produced upon the atmosphere around, and particularlyin front, of a series of spaced conductors bent in the manner described.A device constructed of conductors of such formation, when charged withcurrent, produces a substantial and distinctly perceptible ozonificationof the atmosphere, rarefying the air for an appreciable distance oneither side of the plane of the conductors. The result is a I markeddraft or suction toward the wires, this being so noticeable as to givethe appearance of a magnetic attraction, insects ap proaching the screenbeing drawn forcibly toward it and into the strong electrostatic terracefield in front of it, wherein they are electrocuted before they actuallycome into contact with the wires.

Other objects and advantages of my invention will be apparent from thefollowing specification and drawings, in which like numerals refer tolike parts throughout the several views, and in which Figure 1 is a sideelevational view of an-' insect electrocutor' of the screen typeconstructed in accordance with my invention and showing the preferredform of conductor elements.

Figure 2 is a similar view of an insect electrocutor, also showing thepreferred form of conductors similarly arranged but attached to thesupport in a different manner.

Figure 3 is a broken enlarged horizontal sectional yiew on line 3-3- ofFig. 2, showing the preferred manner of crimping or corrugating theconductors.

Figure 4 is an enlarged fragmentar s'imilarto Fig. 1, showing a modifiedof conductor element. a

Figure 5 is a view similar to Fig. 2, showing the form of conductor ofFig. 4 secured view form to the support in the manner illustrated in 5electric conductors.

Figure 6 is a view similar to Fig. 2, show-' ing a different arrangementof the conductors.

Figure 7 is a perspective view of a cage type-of insect electrocuton,showing my preferred form of conductor element.

Figure 8 is a view similar to Fig. 7, showing my preferred form ofconductor element applied to a specifically different form of device ofthe cage type.

In the drawings m invention is shown applied to supportmg ames ofseveral shapes and types. These frames are employed merely asillustrative examples, the invention being adapted for use in any insectelectrocuting device wherein there are spaced The shape, size orconstruction of the support for the conductors is unimportant. Theinvention resides in the use of spaced electric conductors of thecharacter and configuration described, and they may be held upon asupport of any suitable character. The preferable form of suport is anopen' frame of one of the types illustrated. The conductors, however,may be stretched across an opening in a door or windo or across anyopening of suitable size to t e walls of which the conductors can befastened in taut condition. (Jr, the conductor elements may even bestretched upon I are securely held oppositely supporting strips,preferably 0 and secured to a suitable imperforate support, such as aflat board.

By we of illustration I have, in Figs. 1 to 6 inc usive, shown in theinvention applied to a rectangular frame 1 within which dis osed,wireinsulating material. tween the strips are stretched, in spacedparallel relation, the conductor elements,wh1ch are preferably of steelor spring tensioned alloy. The conductorsmay be in the form of wires orthin narrow metallic 7 The wire-supporting members may be made of wood,fibre-board or other suitable sheet insulatingmaterial, or may be ofrubber, pyroxylin or any other suitable composition molded to shape.They may be made in the form of a single unitary strip, or as aplurality of strip sections.

In Figs. 1 and 4 the wire-supporting strips 2 are provided with rows ofheads or projections 3, about which the wires 4 and 5 may be turned orlooped, and by which the several lengths of wire may be securely held.These heads or projections may be located upon either or both of thefaces of the supporting strips. Their form and construc-- tionconstitute an invention for which I have made application for LettersPatent, said application being Serial No. 246,47 5, filed January 13,1928 co-pending herewith. By the use of supporting strips of thisgeneral character, the strands or lengths or reverse bends of the Wires4 and 5, formed by looping the wiresback and forth across the framearound oppositely disposed supporting heads or projections 3, will liein spaced parallel relation, all in the. same plane. By supporting oneWire upon projections on one side of the strips and the other wire uponprojections on the opposite side, the parallel lengths of the two wireswill be in alternating arrangement throughout the screen. The wiresupporting projections may be so arranged and dimensioned that adjacentwires of opposite polarity will be sufficiently close together toprevent insects from passing between them without bridging the circuitand from the ordinary house lighting circuit, I

through a suitable transformer 15 to the opposite poles of which thewires 4 and 5 may e respectively connected.

Each of the wires 4 and 5 is formed with a k series of bends in it whichare preferably re-v peated at short intervals. throu hout its en-' tirelength. These bends may produced questionably effective in bringingabout the electrical phenomena and advantageous results hereinbeforedescribed.

Like results are obtained by using separate lengths of wire instead ofthe pair of looped wires arranged with their lengths or runs in parallelrelation, as shown in Figs. 1 and 4. Figs. 2, 5 and 6 show severaldifferent modes of arrangement of such separate parallel lengths ofwire. In Fig. 5 the wires illus trated are of the spiral or helical formdepicted in Fig. 4. In the other views the wires are shown as crimped,waved or corrugated.

By way of example, these wires are shown applied to a rectangular framesimilar to that illustrated in Figs. 1 and 4. The wires 4a,

5a are supported by wire-supporting strips 2a, generally similar tostrips 2, the ends of the wires being secured to the strips in anysuitable and convenient manner, preferably by being run throughapertures or grooves in the strips or by being looped around orotherwise fastened to projections upon the opposite faces of the strips.

Fig. 2 shows the horizontal positioning of the wires, which will in mostinstances be found convenient and preferable. In this illustrativeexample, the bends in the wire may he as shown in Fig. 2, or in theposition indicated in Fig. 3, wherein the corners or ends of the bendspoint outwardly and lie in parallel planes on either side of the frame.This manner of forming and arranging the bends has been found to producethe best results. It may be accomplished by means of dies, applied toall of'the wires simultaneously after they have been secured in theframe. Other methods .of crimping or corrugating may be used, however,and good results may be obtained by crimping the wires before they areplaced upon the screen (as in Figs. 1, 2 and 6), in which event thedirection the bends will take will tend to deviate somewhat from theuniform arrangement shown in Fig. 3. Either method of crimping may beemployed, as the uniformity indicated in Fig. 3, although advantageous,is not necessary.

The disclosure contained in Fig. 6 differs from that of Fig. 2 only inthe arrangement of the wires, Fig. 6 showing them in vertical position.

Fig. 5 illustrates a frame similar to the frame shown in Figs. 2 and 6,with spiral instead of crimped wires supported thereon.

The invention may be applied to insect electrocuting devices of othertypes, including devices of the lamp or cage type, examples of which areshown in Figs. 7 and 8. In Fig. 7 the device is in the form of afrusto-pyramid, while in Fig. 8 a frusto-conical cage is illustrated. Ineither of these forms the wires may be secured upon the frame of thedevice in Various ways. For example, the frame 11 may be made of glassor other suitable insulating material, or'if of metal, may be providedwith means for properly insulating the wires from the frame, and thewires may, in either instance, be stretched around the frame, preferablyin grooves provided for this purpose. Or the frame may be made with ribsdefining panels having insulating strips at opposite sides of eachpanel, upon which the wires may be supported in a manner similar to thatillustrated in Fig. 1 or in Fig. 2. Insects are attracted to the deviceby a lamp within the frame.

The form and construction of the devices illustrated in Figs. 7 and 8constitute the subject-matter of a separate application, and need beconsidered herein only as diagrammatic disclosures. They are mentionedhere merely as illustrative examples of possible applications of thepresent invention in additionto its use upon a flat rectangular formsuch as that shown in the other figures.

As will be apparent, the drawings do not show all of the various formsof insect electrocuting. devices to which the presentinvention may beapplied. The invention consists of the novel form of device composed ofa plurality of wires provided in any suitable manner with a series ofbends of the general applicability to insect electrocuting devices inwhich spaced electric wires are employed.

I claim:

1. An insect electrocutor comprising a frame having spaced wiresupporting members, a plurality of spring wires stretched in parallelrelation between said supporting members, and means for supplyingadjacent' lengths of wire with current of opposite polarity.

2. A frame comprising spaced insulating members, wires stretched betweenand supported by said members in spaced parallel relation, and means forsupplying current of opposite polarity to alternate wires, each of saidwires having a series of bends therein between its points of support,whereby the resulting electrostatic field is increased and the wire isinherently spring-tensioned.

3. In an insect electrocutor, a plurality of parallel lengths or runs ofinherently springtensioned wire, and means to supply the adjacentlengths or runs with current of opposite polarity.

4. In an insect electrocutor, a plurality of parallel lengths or runs ofwire, each length or run having spring-tensioning transverse bendstherein intermediate its ends, and means for supplying current ofopposite polarity to adjacent lengths or runs of said wires.

5. An insect electrocutor comprising a support, and a plurality oflengths of inherently spring-tensioned wire stretched in substantiallyparallel relation upon said support, alternate lengths being arranged toreceive current of opposite polarities.

6. An insect electrocutor comprising spaced wire-supporting members. anda plurality of inherently spring-tensioned wires stretched insubstantially parallel relation between said members.

7 An i'n'sect electrocutor comprising a support, and a plurality oflengths of crimped wire stretched in substantially parallel relationupon said support, the inherent spring tension of said lengths of wiremaintaining such relation under varying atmospheric conditions, and thecrimped nature of the wire enlarging the electrostatic field.

8. An insect electrocutor comprising spaced wire-supporting members, anda plurality'of crimped spring wires stretched in substantially parallelrelation between said members, adiacent lengths of said wires beingarranged to receive current of opposite polarity.

9. An insect electrocutor comprising a support, and a plurality ofspirally-wound spring wires stretched insubstantially parallel spacedrelation upon said support. alternate lengths or runs of said wiresbeing arranged to receive current of opposite polarities. v

10. An insect electrocutor comprising a support. and a plurality oflengths or runs of coil spring wire stretched in substantially parallelspaced relation upon said support and respectively arranged to receivecurrent of opposite polarities.

11. An' insect electrocutor comprising spaced wire-supporting members,and a plurality f lengths or runs of coil spring wire stretched insubstantially parallel relation between said members. 12. In an insectelectrocutor, a suppo comprising s acedinsulating members. a pluralityof lengths or runs of "coil spring wire stretched between and supportedby said members in spaced parallel relation, and

means for supplying current of opposite polarity to alternate lengths'orruns.

13. In an insect electrocutor. spaced supporting members, a plurality ofsubstantially parallel lengths or runs of coil spring wire supported instretched condition between said members, and means for supplyingcurrent of opposite polarity to adjacent lengths 14. In an insectelectrocutor, aframe havmg an opening therein, coil "spring wiresstretched across said opening in spaced parallel relation, means forinsulating said wires, and means for supplying current of oppositepolarity to alternate wires.

WILLIAM M. FRQST.

